• Title/Summary/Keyword: 운석

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A Study of the Potential Shelters in the Lunar Lava Tubes (달 동굴의 잠재적 주거환경에 관한 연구)

  • Oh, Jongwoo
    • Journal of Satellite, Information and Communications
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    • v.12 no.3
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    • pp.41-49
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    • 2017
  • This paper will describe lunar lava tubes' five analyzed fields, such as geology, geomorphology, internal configuration, stability, communication and habitats requirements. This research gets through qualitative and qualitative data analysis as following results. A huge size and configuration differences between lunar lava tubes and earth one on geology and landform environments. Exo-genetics activities, such as meteorites, radiation, and sudden temperature bigger affect than Endo-genetic activities, such as effusion and earthquake of the lunar lava tubes. Landform and internal configuration of the lunar lava tubes due to the huge cave perilous landform that gravity difference have a technical limitation from internal approach and data obtain of the huge skylights and sinuous rilles. Stability of the lunar lava tubes deals with geology and landform. It was obvious geo-structural stability elements results generated on low rate of collapsed halls(skylights), low gravity, and relatively thick covers. In terms of the communication capability on the external and internal lunar lava tubes cordless communication techniques will overcome limitations of the sun-power generates supporting communication systems. Through this research it realized obvious differs between potential habitats possibility by accumulative theories by scholars and techniques of the lunar lava tubes. Especially, it is a favorable expectation throughout overcoming attempt on zero gravity, cosmo radiation, lunar dust of the exo-genetic limitations to the steep escarpment of skylights to approach and achieve techniques by the civil engineering, networking and GIS techniques as the endo-genetic environment treatment.

Occurrence and Mineralogical Characteristics of Asbestos in Dolostone at Ungdo, Seosan (서산 웅도 백운암 내 석면 산출 및 광물학적 특성 규명)

  • Kim, Seon-Ok;Lee, Minhee;Jung, Hyunjung;Shin, Wonji
    • Economic and Environmental Geology
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    • v.47 no.5
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    • pp.489-496
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    • 2014
  • The occurrence and mineralogical characteristics of asbestos in dolostone at Ungdo, Seosan were investigated by analyses of PLM, XRD, and SEM/EDS. Representative outcrops of dolostone at Ungdo were examined and four dolostone samples were collected according the occurrence type to identify the shape of asbestos in dolostone samples. The host rock of dolostone had been produced from the hydrothermal alteration and/or thermal metamorphism of which main source was assumed as the acidic granite. Tremolites were observed near the cracks or fractures of the dolostone as tamping or gob types. From the mineralogical analyses, main minerals of dolostone were dolomite with calcite, quartz, talc, amphibole, and pyroxene. From SEM/EDS analyses, tremolite-actinolite asbestoses were observed in dolostone and their shapes were prismatic and fibrous (less than $1{\mu}m$ in width). Non-asbestos prismatic forms were also found and they would transfer to asbestos particles resulting from the cleavage and fracture of the prismatic particles. Overall results suggest that asbestoses in Ungdo dolosotnes were mainly tremolite-actinolite and they were originated from the hydrothermal alteration of Ca-Mg rich dolostone.

A Study on the Heavy Metal Contamination of paddy Soil in the Vicinity of the Seosung Pb-Zn Mine (서성 연-아연광산 주변 농경지 토양의 중금속 오염 연구)

  • 황은하;위수민;이평구;최상훈
    • Journal of Korea Soil Environment Society
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    • v.5 no.2
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    • pp.67-85
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    • 2000
  • Fifty seven soil samples were collected from the paddy soil filled with tailings in the vicinity of the Seosung Pb-Zn mine. Those samples were analyzed for As, Cd, Co, Cr, Cu, Pb, and Zn in order to investigate heavy metal pollution levels in the paddy soil. Analyses of the soil samples were carried out using Inductively Coupled Plasma Atomic Emission Spectrometry(ICP-AES) . Paddy soils show pH range from 6.55 to 8.26. X-ray diffraction analyses of the paddy soil indicate that the soils consist predominantly ankerite, siderite, quartz, mica, and clay minerals with minor amounts of amphibole and chlorite. The mineral composition of the waste rocks consists of massive galena, sphalerite, and minor amounts of pyrite, arsenopyrite, chalcopyrite, calcite, siderite, Pb-sulfosalt, and marcasite. The paddy soils were significantly contaminated by heavy metals(average concentrations, As: 334.4 ppm, Cd: 37.6 ppm, Co: 15.7 ppm, Cu: 214.1 ppm, Pb: 4,612 ppm, and Zn: 4,468 ppm).

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The effect of call center agent job characteristics on turnover intention : focused on moderating effect of self leadership (콜센터 상담직원의 직무특성이 이직의도에 미치는 영향 : 셀프리더십의 조절효과를 중심으로)

  • Oh, Jong-chul;An, Un-seok
    • Journal of Venture Innovation
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    • v.1 no.1
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    • pp.145-164
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    • 2018
  • The purposes of this study was to investigate job related attitudes of emotional labors working at call centers in Korea. The attitudinal variables were burnout, psychological capital and turnover intention with job characteristics as the independent variables. In addition, leadership behaviors of the superiors, self leadership behavior in particular, was incorporated to see if it has any bearing on these relationship as moderating variable. Data has been collected from 543 respondents for this study using questionnaire method. The survey for the actual analysis of the research was done and analyzed with the employees who work for contact centers in Seoul, Busan, and Gwangju, Korea. The survey was done for 24 days from November, 2016 through December, 2016. * The following study results were revealed: First, the job characteristics does not have direct positive effect on turnover intentions. Second, the job characteristics were related positively to job burnout. Third, the job burnout does mediate the relationship between job characteristics and turnover intentions. Lastly, results of research on the moderating effect of self leadership in relationships between emotional labor, job burnout, psychological capital and turnover intention show that super leadership has only a limited regulatory effect between job characteristics and turnover intention.

A Study on the Improvement of Health Damage Relief Regulation due to Environmental Hazardous Factors (환경유해인자로 인한 건강피해 구제제도의 개선방안에 관한 고찰)

  • Baek, Woonsuk;Shim, Younggyoo
    • Journal of Environmental Policy
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    • v.12 no.1
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    • pp.75-100
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    • 2013
  • Health damages such as pneumoconiosis and kidney damage, caused by environmental hazardous factors are being reported in health impact assessment conducted on environmentally vulnerable areas, including cement factories and refineries. Current legal system for relieving the environmental victims is not effective enough because the environmental health act does not specify the environmental hazardous factors to be considered for the relief. The aim of this study is to examine the problems of the existing system by making empirical analysis on health damages and afflicted people as well as on cases when afflicted people were able to be covered by remedy system. The results show that, insufficiencies of the relief system are due to the following reasons: First, current Environmental Health Act does not act well as a remedy system. Second, due to its unique nature of environmental health damage, it is hard to identify and prove the cause of health damage and unlawful actions of violators in the process of environmental dispute conciliation and lawsuits against polluters. This paper suggests following solutions on above mentioned problems. First, in defining the range and definition of environmental diseases, negative system should be used alongside with the current positive system. Second, we suggest adding the nature of public law to relief system, in order to ease the legal burden of proof. Third, in case when it is hard to identify the polluters and one cannot expect reliefs for their damage, it is possible to elevate the effectiveness of the relief measure by expanding scope of the search for possible environmental hazardous factors that caused the health damage. It is urgent to improve the relief system so as to secure the environmental rights of Koreans.

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Ettringite/Thaumasite Formation, Stability and Their Effect on Deterioration of Concrete (에트린자이트/사우마사이트의 형성 및 안정도와 콘크리트 성능저하에 미치는 영향)

  • 이효민;황진연
    • Journal of the Mineralogical Society of Korea
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    • v.16 no.1
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    • pp.75-90
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    • 2003
  • Ettringite and thaumasite were observed in some concrete. The morphology and occurrence of these minerals were closely examined by performing SEM/EDAX analyses. We also experimentally induced the concrete deterioration using $Na_2SO_4$ solution with application of various environmental conditions. The stability of these minerals and deterioration characteristics under applied experimental conditions were determined. Abundant ettringite formed by“through solution reaction”occurred in many open spaces, and some microscopic ettringite formed by "tophochemical replacement" of calcium aluminate also occurred in cement paste. Severe cracking of cement paste causing premature deterioration was often associated with ettringite location. Under specific condition, ettringite was transformed to thaumasite, tricthloroaluminate, or decomposed. Thaumasite occurred with association of ettrinsite in concrete containing carbonate aggregate being subject to dedolomitization or in some concrete being subject to carbonation. Thaumasite appears to be formed under the similar condition to the general ettringite forming condition, but it formed solid solution with ettringite by substituting pre-existing ettringite. Ettringite can also be transformed to trichloroaluminate in the presence of abundant chlorides, but trichloroaluminate changed back to ettringite in late sulfate attack. It is considered that the substitution reaction direction solely depend on the concentration of chloride and sulfate ion.

The Effects of Web-based Education and Individuals Characteristics to Participants Commitment and Educational Performance (웹기반 교육 특성과 개인적 특성이 학습자 몰입과 교육성과에 미치는 영향 - 급식관리자 웹기반 교육을 중심으로 -)

  • Cho, Jae-Yong;An, Un-Seok;Jang, Hyung-Sub
    • Management & Information Systems Review
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    • v.28 no.4
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    • pp.1-26
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    • 2009
  • Among food-service managers, a survey was conducted to grasp the their work-related education conditions and the demand for education program development. This study focuses on food-service managers in web-based training and analyzes the critical factors involved in their learning process in order to clarify the factors that lead to the maximization of training programs. The results of all this study process are as follows. First, the characteristics of web-based education including component of education factor, system factor, deepening learning factor have meaningful effect on commitment of the participants and education performance(except deepening learning factor to education performance). Second, the analysis that the characteristics of individuals including self-efficacy in learning, purpose-directivity factor have meaningful effects on commitment of the participants and education performance(except purpose-directivity factor to education performance). Third, commitment of the participants has meaningful effects on the education performance. Thus, it is advisable for education managers or operators to emphasize in foodservice organizations.

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An Efficient Periodic-Request-Grouping Technique for Reduced Seek Time in Disk Array-based Video-on-Demand Server (디스크 배열-기반 주문형 비디오 서버에서의 탐색 시간 단축을 위한 효율적인 주기적 요청 묶음 기법)

  • Kim, Un-Seok;Kim, Ji-Hong;Min, Sang-Ryeol;No, Sam-Hyeok
    • Journal of KIISE:Computer Systems and Theory
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    • v.28 no.12
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    • pp.660-673
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    • 2001
  • In Video-on-Demand (VoD) servers, disk throughput is an important system design parameter because it is directly related to the number of user requests that can be served simultaneously. In this paper, we propose an efficient periodic request grouping scheme for disk array-based VoD servers that reduces the disk seek time, thus improving the disk throughput of VoD disk arrays. To reduce the disk seek time, the proposed scheme groups the periodic requests that access data blocks stored in adjacent regions into one, and arranges these groups in a pre-determined order (e.g., in left-symmetric or right-symmetric fashion). Our simulation result shows that the proposed scheme reduces the average disk bandwidth required by a single video stream and can serve more user requests than existing schemes. For a data block size of 192KB, the number of simultaneously served user requests is increased by 8% while the average waiting time for a user request is decreased by 20%. We also propose an adaptation technique that conforms the proposed scheme to the user preference changes for video streams.

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Effects of Soil Amendments on the Early Growth and Heavy Metal Accumulation of Brassica campestris ssp. Chinensis Jusl. in Heavy Metal-contaminated Soil (중금속 오염 토양에서 안정화제가 청경채의 초기 생육과 중금속 흡수량에 미치는 영향)

  • Kim, Min-Suk;Koo, Namin;Kim, Jeong-Gyu;Yang, Jae-E.;Lee, Jin-Su;Bak, Gwan-In
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.961-967
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    • 2012
  • There have been many studies about efficiency of amendments for heavy metal stabilization through chemical assessment. The objective of this study was to evaluate the efficiency of several soil amendments (lime, agric-lime, dolomite, steel slag, fly ash and acid mine drainage sludge) on heavy metals stabilization through not only chemical but also biological assessments (phytotoxicity test) in abandoned mining area soil. In order to achieve the goal, we conducted preliminary screening experiment targeting 12 types of crop plants such as radish, young radish, chinese cabbage, winter grown cabbage, cabbage, bok choy, chicory, crown daisy, carrot, chives, spinach, and spring onion. The results of inhibition rates of early plant growth in metal-contaminated soil against non-contaminated soil and the correlations between inhibitions items showed that the bok choy was appropriate specie with respect to confirm the effect of several amendments. Several amendment treatments on contaminated soil brought about the changes in the root and shoot elongation of bok choy after 1 week. Agric-lime, dolomite and steel slag treatments showed the great efficiency of reducing on mobility of heavy metals using chemical assessment. But in contrary, these treatments resulted in the reduction of root and shoot elongation and only AMD sludge increased that of elongation, significantly. When considering both chemical and biological assessments, AMD sludge could be recommended the compatible amendment for target contaminated soil. In conclusion, biological assessment was also important aspect of decision of successful soil remediation.

Effects of Furosemide on perioperative Serum Osmolality and Electrolytes during Transurethral Resection of the Prostate (경요도 전립선 절제술시 투여한 Furosemide가 수술중, 후 혈중 나트륨 및 삼투질농도에 미치는 영향)

  • Kim, Sae-Yune;Roh, Un-Seok;Park, Dae-Pal
    • Journal of Yeungnam Medical Science
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    • v.9 no.1
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    • pp.110-120
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    • 1992
  • The purpose of this study was to prevent the dilutional effect of excessive absorption of irrigating solution by using furosemide intraoperatively during transurethral resection of the prostate, 30 patients, who belonged to physical status II or III of ASA classification, were selected randomly and divided with two groups as follows : G1(N=15) : Not-administrated furosemide(control group) G2(N=15) : Administrated furosemide(Experimental group). All patients were premedicated with Hydroxyzine(1mg/kg, IM) and were performed continous epidural anesthesia with 2% lidocaine(1-1.5mg/segment). For irrigating solution, 5% D-sorbitol was used and Hartman's solution were given for maintenance fluid and fixed the height of irrigating container to 60 cm from symphysis pubis. With the starting of operation, 20mg furosemide was administrated to experimental group. The blood samples for the values of $Na^+$, $K^+$, Glucose and BUN were performed at the periods of preoperation, 10 min, 20 min, 30 min after the starting of operation and immediate postoperation. Based these data, serum osmolality and effective osmolality were calculated. The results were as follows : 1. The sodium concentration of control group was decreased statistically significantly at 10 min, 20 min, 30 min after the starting of operation and immediate postoperative period as comparing with the preoperation value(p<0.05). But that of experimental Group was not changed significantly. 2. The serum osmolality and effective osmolality were decreased statistically significantly at 30 min after the starting of operation and immediate postoperative period as comparing with the preoperation value(p<0.05). But those of experimental group were not changed significantly. These results show that the dilutional effect of excessive absorption of irrigating solution might be prevented by using furosemide intraopertively. And so we recommend the use of furosemide during TURP, especially in patients with congestive heart failure or renal failure.

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